题解 | #表达式求值#

import java.util.Scanner;
import java.util.Map;
import java.util.HashMap;
import javax.script.ScriptEngineManager;
import javax.script.ScriptEngine;
import javax.script.ScriptException;
// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) throws ScriptException {
        Scanner sc = new Scanner(System.in);
        ScriptEngine nashorn = new ScriptEngineManager().getEngineByName("nashorn");
        System.out.print( nashorn.eval(sc.next()));
    }
}